Will an expunged record affect my ability to get a top secret security clearance?

3 years ago I was accused of 2nd degree assault. The details of the case were a mess and it was basically thrown out of court because the accusers couldn't prove they had actually accused the right person. They even had my name and description wrong. I was never arrested or convicted. I got the record of the case expunged so that it wouldn't ever show up in my background. I just joined the army and my MOS will require a top secret clearance. On the form I had to fill out I answered 'no' to all of the legal matters questions because I was never arrested or convicted. I understand that the investigators will be able to see that I had something expunged, but will it affect my ability to get a top secret clearance? Thanks!!